Doctor profile · Federal record
Dr. Maruja Diaz Arjonilla, MD
Endocrinology, Diabetes & Metabolism Physician (CMS: Endocrinology) · Santa Ana, CA
- NPI 1841481074
- Accepts Medicare
- 36 yrs in practice
- Female
- Group practice
- No sanctions
Practice & contact
Operates at 2 locations .
- Primary practice
-
2212 E 4Th St Ste 304
Santa Ana, CA 92705
(714) 288-3230
fax (714) 571-7719 - Additional location
-
1160 Sunset Blvd
Rocklin, CA 857653772
(916) 865-1000
fax (816) 865-1005
Credentials & registration
- NPI registered
- August 2007 — 19 yrs on file
- Profile last updated
- October 21, 2020
- Year of graduation
- 1990 — 36 yrs since
- Specialty taxonomy
- 207RE0101X — NUCC code
- State license (1)
- California #A97144
Federal sanctions & exclusions
No sanctions, exclusions or revocations on file
Checked against OIG LEIE on NPI 1841481074. Last verified May 11, 2026.Medicare procedures · 2023
Top services delivered
Total services
335
Distinct HCPCS
5
Medicare allowed
$38,339
| HCPCS | Description | Services | Patients | Avg allowed | |
|---|---|---|---|---|---|
99214 |
Established patient office or other outpatient visit, 30-39 minutes | 212 | 88 | $139 | |
99232 |
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | 51 | 21 | $83 | |
82962 |
Blood glucose (sugar) test performed by hand-held instrument | 26 | 22 | $3 | |
76536 |
Ultrasound scan of head and neck soft tissue | 24 | 22 | $102 | |
99213 |
Established patient office or other outpatient visit, 20-29 minutes | 22 | 16 | $98 |
In context: peer comparison
Among 2 peers in Santa Ana Endocrinology, Diabetes & Metabolism Physician, average services per provider: 52. This provider delivers 6.4× the peer median.Open Payments
Industry payments received
All-time total
$143
Transactions
8
Manufacturers
7
| Payer (manufacturer) | Industry | Txns | Amount |
|---|---|---|---|
| Insulet Corporation | 1 | $29.75 | |
| Abbott Laboratories | 2 | $29.01 | |
| Xeris Pharmaceuticals, INC. | 1 | $22.49 | |
| Lilly USA, LLC | 1 | $22.40 | |
| Embecta Corp. | 1 | $17.93 | |
| Medtronic, INC. | 1 | $13.08 | |
| Beta Bionics, INC. | 1 | $8.69 |
By nature of payment
Medicare Part D · 2023
Top prescriptions
Total claims
2,163
Patients
647
Total drug cost
$1,006,861
| Drug | Type | Claims | Patients | Total cost |
|---|---|---|---|---|
| Levothyroxine Sodium | Generic | 358 | 103 | $8,905 |
| Lantus Solostar (Insulin Glargine,Hum.Rec.Anlog) | Brand | 302 | 85 | $193,031 |
| Metformin Hcl ER (Metformin Hcl) | Brand | 285 | 94 | $7,268 |
| Glipizide ER (Glipizide) | Brand | 224 | 63 | $5,124 |
| Trulicity (Dulaglutide) | Brand | 200 | 46 | $295,175 |
| Nano 2Nd Gen Pen Needle (Pen Needle, Diabetic) | Brand | 160 | 67 | $15,770 |
| Humalog Kwikpen U-100 (Insulin Lispro) | Brand | 98 | 36 | $79,528 |
| Ozempic (Semaglutide) | Brand | 95 | 22 | $127,893 |
| Atorvastatin Calcium | Generic | 79 | 24 | $1,328 |
| Januvia (Sitagliptin Phosphate) | Brand | 74 | 22 | $102,102 |
Hospital affiliations
Frequently asked questions
What is Dr. Maruja Diaz Arjonilla's medical specialty?
Dr. Maruja Diaz Arjonilla practices Endocrinology, Diabetes & Metabolism Physician in Santa Ana, CA.
Where does Dr. Maruja Diaz Arjonilla practice?
Dr. Maruja Diaz Arjonilla practices at 2212 E 4Th St Ste 304, Santa Ana, CA 92705. Office phone: 7142883230.
What is Dr. Maruja Diaz Arjonilla's NPI?
Dr. Maruja Diaz Arjonilla's National Provider Identifier (NPI) is 1841481074, issued by NPPES.
Does Dr. Maruja Diaz Arjonilla accept Medicare assignment?
Yes. Dr. Maruja Diaz Arjonilla accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Maruja Diaz Arjonilla commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Blood glucose (sugar) test performed by hand-held instrument (HCPCS 82962). Source: CMS Medicare Physician & Other Practitioners file.